Blower fans



Oct. 22,A 1957 J. R. MCVEIGH BLOWERFANS Filed May '7, 1954 INVENTOR. 7m P. MC1/ggz BY my United States Patent l "f BLOWER FANS John R. McVeigh, Yardley, Pa.

Application May 7, 1954, Serial No. 428,152

6 Claims. (Cl. 230-134) My present invention relates to a blower fan and more particularly to the specific construction thereof whereby to provide a fan adapted for withstanding relatively high temperatures, such as are present in a high temperature gas or electric furnace.

There are many applications where fans are needed to directly circulate air in a high temperature, but heretofore such fans have been made of special steel alloys which have limited the temperature at which they can be operated. Such fans have been made of one piece integral structures as well as of fabricated structures.

It is an object of my present invention to overcome the above temperature limitation by providing a fan structure capable of operation at considerably higher temperatures than heretofore possible. Further, my construction takes into consideration the characteristics of high temperature materials such as bonded titanium carbide as Well as to keep the cost of the structure down to an acceptable economical level. For instance, it would be impossible, or at least the expense would be prohibitive, to make such fans of the bonded titanium carbide (powder metallurgy) to existing designs. On the other hand, my invention does provide for a fabricated assembly of parts most easily made of -a bonded carbide material with a minimum of finish required after sintering.

For a more detailed understanding of my invention reference may be had to the accompanying drawings illustrating a preferred embodiment thereof in which like characters refer to like parts throughout the several views, and in which Fig. l is a longitudinal sectional view of my improved fan construction taken substantially on the line 1-1 of Fig. 2;

Fig. 2 is a transverse sectional viewthrough the fan blades taken substantially on the line 2--2 of Fig. 1, and

Fig. 3 is a further detail transverse sectional view taken on the line 3-3 of Fig. 1.

The assembled fan structure as herein illustrated is indicated generally by the reference character 10, and is shown installed in a high temperature furnace 11, the fan assembly having a drive shaft 12 supported in a suitable bearing 14 in the furnace wall and carrying a driving gear 15 or other suitable driving means externally of the furnace. The shaft 12 has a fan hub 16 secured thereto, and said hub supports a plurality of separate fan blades 17.

The aforesaid hub structure is provided with a plurality of longitudinal slots receiving and locating the fan blades 17, and said slots and fan blades are grooved respectively as at 21 and 22 to receive an interlocking pin 23 which secures the blades in the slot, the centrifugal forces when the fan is rotating serving to bind the blades more securely to the hub. The fan blades are preferably made of extruded material, such as bonded titanium carbide, and the simple machining required is done to the blades before sintering. The hub structure is also preferably made of bonded titanium carbide.

The outer end of the hub 16 is solid as said slots termi- 2,810,513' Patented Oct. 22, 1957 ICC nate short of the'end thereof, thereby providing an abutment 16a engaging one edge of said fan blades. The inner face of the hub has an undercut button 25, the inner face of the annular groove 26 in this button being preferably nish ground as desired after sintering.

The shaft 12 is provided with an enlarged inner end portion or flange 30. and the inner face thereof is recessed as at 31 and provided with an axial bore 31 and counterbore 32. The button 25 of the hub is received in the counterbore 32 and a split coupling 33 having radially inwardly extending flanges 33a and 33b respectively engage the groove 26 and the enlarged head 35 of the bolt .36, a nut 37 screw-threaded on said bolt tightly connecting the hub 16 to the drive shaft. Driving torque is transmitted from the shaft 12 to the hub 16 by means of dowels or pins 40, which are secured to the flange 30 and are engaged iu the slots 20 of the hub. The tightening of the nut 37 draws the hub structure into tight abutting contact with the inner face of this shaft flange 30. The blades 17 may be made of one piece or in sections. Any broken blades may be very readily replaced as said hub and blades are very easily detached from the shaft 12. The whole assembly is quickly and securely fastened together, said split collar or coupling 33 facilitating the assembly.

It will be apparent to those skilled in the art to which lmy invention pertains that various changes and modifications may be made therein without departing from the spirit of my invention as herein shown or fromV the scope of the appended claims.

I claim:

1. A blower fan for a high temperature furnace or :other similar application and comprising a fan hub constructed of a bonded carbide material, fan blades of an extruded bonded carbide material and secured to said hub and extending radially with respect thereto, said hub structure and fan blades being resistant to relatively high temperatures, a drive shaft for said blower fan and adapted to extend through a wall of said high temperature furnace and having an enlarged flange provided with an inner machined end face provided with a recess, said flange andface disposed interiorly of said furnace, Ymeans securing the hub to said drive shaft and means drivingly connecting said hub and drive shaft to directly transmit driving torque, said securing means comprising an axially disposed undercut button extension carried by the hub, an adjustable lock bolt axially carried by said drive shaft and having an enlarged flange on the end thereof disposed in Y abutting juxtaposition with respect to said button, and a split collar coupling said button .and'bolt flange, the peripheral wall of said split collar being substantially engaged thereabout by the wall of said recess, said adjustable `lock bolt being tightened and axially adjusted to clamp said hub in tight abutting contact with the machined end face of the flange'carried by said drive shaft.

2. A blower fan comprising a hub structure and a plui rality of fan blades secured to the hub structure, said hub structure and blades constructed of a bonded carbide material resistant to relatively high temperatures and thereby adapted for assembly interiorly of a high temperature furnace or other similar application, a drive shaft for said fan and adapted to extend through a wall of said furnace and having a machined inner end face provided with -a recess, said hub structure having an axially extending undercut button extension, an adjustable bolt axially carried by said shaft and having a flange on its inner end adjacent to and in axial alignment with the button carried by said hub, and a split collar coupling said button and bolt flange, the peripheral Wall of said split collar being substantially engaged thereabout by the wall of said recess, said adjustable bolt being tightened and axially adjusted 3 t to clamp said hub in tight abutting contact with theY machined end face of said drive shaft.

3. A blower fan comprising a hub structure and a plurality of fan blades secured to theliubstructure, said hub structure and blades constructed of a bonded carbide material resistant to relatively high temperaturesand thereby adapted for assembly interiorly of a high temperature furnace or other similar application, a drive shaft for said fan and adapted to extend through a wall of said furnace and having a machined inner end face, said hub structure having an axially extending undercut button extension, an adjustable bolt axially carried by said shaft and having an enlarged flange on the end thereof adjacent tor and in axial alignment with said button, and a split collar couplingsaid button and bolt liange, said adjustable bolt being tightened and axially adjusted to clamp said hub in tight abutting contact with the machined end face of said drive shaft, said shaft having a recess extending axially inwardly of the machined end face, said button, bolt ange and split collarassembly substantially housed within said recess, the peripheral wall of said split collar being substantially engaged thereabout by the wall of said recess.

4l A blower fan comprising a hub structure and a plurality of separable fan blades secured to the hub structure, said hub structure and blades constructed of a bonded carbide material resistant to relatively high temperatures and thereby adapted for assembly interiorly of a high temperature furnace or other similar application, a drive shaft for said fan adapted to extend through a wall of said furnace and having a machined inner end face,said hub structure having an axially extending undercut button extension, any adjustable bolt axially carried by said shaft and having an enlarged flange on the end thereof adjacent to and in axial alignment with said button, and a split collar coupling said button and bolt flange, said adjustable bolt being tightened and axially adjusted to clamp said hub and separable blades in tight abutting Contact with the machined end face of said drive shaft, said shaft having a recess extending axially inwardly of the machined end face, said button, bolt ange and split collar assembly substantially housed within said recess, the peripheral wall of said split collar being substantially engaged thereabout by the wall of said recess, said shaft having an axial longitudinal bore to accommodate said bolt, said adjustable bolt having an adjustable nut threaded onto the end thereof remote from said iiange permitting the coupling of said fan and shaft from without the furnace.

5. A blower fan comprising a hub structure and a plurality of separable fan blades secured to the hub structure, said hub structure and blades constructed of a bonded carbide material resistant to relatively high temperatures and thereby adapted forv assembly interiorly of a high temperature furnace or other similar application, a drive shaft for said fan adapted to extend through a wall of said furnace and having a machined inner end face, said hub structure having an axially extending undercut button extension, an adjustable bolt axially carried by said shaft and having an enlarged ange on the end thereof adjacent to and in axial abutting alignment with said button, and

A substantially housed within. saidl recess the peripheral wall of said split collar being lsubstantially engaged thereabout by the wall of said recess, said hub having longitudinally extending grooves ony .the exterior cylindrical surface thereof for loosely receiving said fan blades and an abutment limiting displacement of the blades axially away from said end face ofthe shaft flange, said blades and side wall of said grooves having complementary longitudinal keyways and a key interengaged with the said keyways to secure said separable blades to the hub structure against radial displacement,

6. A blower fan and drive shaft therefor for assembly with a high temperature furance and comprising separable fan blades, a h ub structure, and a drive shaft, said drive shaft adapted to extend through a wall of the furnace and constructed of steel, said separable fan blades and hub structure constructed of a bonded carbide material highly resistant to relatively high temperatures such as titanium carbide and of relatively low ductility to facilitate machilling, means securing said fan blades to the hub to limit displacement thereof radially of the hub and longitudinally in one direction, and means drivingly securing said hub to the drive shaft, said last mentioned means comprising an adjustable boltaxially supported by said drive shaft and having an enlarged ange on the inner end thereof, said hub having an undercut button extension axially aligned with said shaft and bolt, and a split collar coupling said bolt and button, said shaft having a machined inner end face and an axial rece-ss for accommodating said bolt ange, hub button and split collar assembly the peripheral wall of said split collar being substantially engaged thereabout by the wall of said recess, said adjustable bolt tightened down to clamp said hub against the machined inner end face of said drive shaft, said hub having longitudinal grooves receiving said fan blades, said drive shaft enlarged inner end portion being of substantially the same diameter as said hub and provided with one or more holes in alignment with a groove in said hub, and a pin carried in said holes of the enlarged inner end portion of the drive shaft and projected into the aforesaid grooves of the hub to drivingly connect said drive shaft and hub, said adjustable bolt'being axially adjusted to clamp'both said hub and the blades carried thereby against the machined end face of the drive shaft.

References Cited in the file of this patent,

UNITED STATES PATENTS 961,328 Wait June 14, 1910 1,181,780 Lowenstein May 2, 1916 2,662,725 McVeigh Dec. l5, 1953 FOREIGN PATENTS 269,605 Switzerland July 15, 1950 

